PrecalculusMrs. Spatola

Name______Date______

Check for understanding quiz

a)Find the domain of the function

b)Find the x and y coordinates of any holes in the graph of the function.

c)Write the equation of any vertical asymptotes.

d)Describe the behavior of the graph as x approaches the asymptote from the left and right. (create a table to observe where the graph is going)

x→ / f(x) / x→ / f(x)

Turn the page over

Write your answer to Homework Question #1 from lesson #16

i)

ii)

iii)

iv) (you do not have to rewrite your table, just describe the shape of the graph)

SWBAT find x & y-intercepts of rational functions.

(Lesson 17 - 3-4)

Finding y-intercepts

If a function - any function is defined at x = 0, then it has a y-intercept; if it is not defined at x = 0, then it does not have a y-intercept. Rational functions, of course, may or may not be defined at zero.

1)For each of the following rational functions, determine whether the function has a y-intercept.

a)If it has a y-intercept, find the location of the y-intercept.

b)If it does not have a y-intercept, determine if it has a hole on the

y-axis or if it has a vertical asymptote at x = 0.

a)

b)

c)

d)

Finding x-intercepts

2)If the equation f(x) = 0 has one or more real roots, where f is any function then the graph of f has an x-intercept at each real root. Like polynomials, rational functions may or may not have real zeros.

  • Find the domain of the function.
  • Find all the real zeros of the numerator. These are the candidates for the x-intercepts.
  • Test each zero. If the zero is in the domain, then it is an x-intercept. Otherwise, it is not.

a)

b)

c)

d)

1